1. Field of the Invention
The present invention relates the field of sound enhancement for mobile phones and other products which produce audio for users, and more particularly to techniques for enhancing sound based upon an individual's hearing profile, based upon environmental factors like noise-induced hearing impairment, and based on personal choice.
2. Description of Related Art
Assessing an individual's hearing profile is important in a variety of contexts. For example, individuals with hearing profiles that are outside of a normal range, must have their profile recorded for the purposes of prescribing hearing aids which fit the individual profile. Typically hearing profile assessments are made by professional audiologists using calibrated and specialized equipment. Therefore, hearing profile assessments have been relatively difficult to obtain and expensive.
A variety of uses for hearing profiles, other than for the purposes of prescribing hearing aids and assistive listening devices, is being developed. For example, hearing profiles of individuals can be utilized for producing customized audio products, such as pre-recorded music that has been modified according to the hearing profile of the listener. One medium for delivering customized audio products is the Internet. See, commonly owned and copending U.S. patent application Ser. No.: 09/464,036, filed 15, Dec. 1999, by Pluvinage, et al., entitled “System and Method for Producing and Storing Hearing Profiles and Customized Audio Data Based on Such Hearing Profiles.”
The mobile phone is a unique class of personal audio device, which presents difficulties to persons with hearing profiles that do not fall within the normal ranges. The most common approach to enabling use of mobile phones for hearing impaired persons involves the use of hearing aids. However, digital mobile phones can cause electromagnetic and acoustic interference with digital hearing aids, forcing removal of aids during mobile phone usage, leaving the user with no compensatory signal processing. In one innovative example, mobile phones can be coupled to inductive neck-worn loops as phone accessories, which deliver signals to electromagnetic receivers called “Telecoils” within hearing aids. However the inconvenience and small market penetration of Telecoils in hearing aids makes them a limited solution. Simply increasing amplification in cell phones is another approach with obvious drawbacks.
Previous people have suggested systems that compensate for apparent hearing loss due to background noise masking. Such prior systems are dependent on the use of microphone input signals to determine the amount of background noise. Some of these systems also teach the use of compression for such compensation. Background information including the use of compression in phones is described in Goldberg (U.S. Pat. No. 4,829,565) and Allen & Youtkas (U.S. Pat. No. 5,553,134), although primarily for noise compensation; other patents include: U.S. Pat. Nos. 5,802,164, 5,539,806, 6,061,431, 5,737,719, 5,388,185, 5,896,449 for telephone signal enhancement; U.S. Pat. Nos. 4,964,304, 6,071,236, 3,974,335, and U.S. Pat. No. 5,737,389 for hearing testing over a phone or telecommunications network.
Mobile phones are inherently personal communication devices. Innovations in microelectronics have allowed mobile phones to become extremely portable and wearable, affording access to telecommunications services wherever the service infrastructure is available. Future generation mobile phones may also incorporate entertainment features such as streaming audio and video, playback of stored audio or video, radio reception and presentation, and many other features that deliver audio to the user. It is desirable to enhance the reception of mobile phone system audio by the user, accommodating personal hearing needs, personal choice, or optimization to the noise environment surrounding the user.